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Cartesian Circle

This blog will be based on an article by Lynn E. Ross, which was called “Cartesian Circle”. It appeared in a philosophical journal called Philosophy and Phenomenological Research, Vol. 26, No. 1 (Sep., 1965), pp. 80-89.

Ross brings up what is said to be the Cartesian Circle.

“Descartes’ reasoning is often said to be circular, in that he deduces the existence of God from clear and distinct perceptions and then deduces the reliability of our clear and distinct perceptions from the existence of God.”

Now Ross is going to try to show that when Descartes uses Clear and Distinct perceptions to prove the existence of God is true, but there is a difference. Descartes is not assuming the reliability of allclear and distinct perceptions. Descartes only presupposes the the reliability of Clear and Distinct perceptions that are known through the “light of nature”, through “metaphysical certainty” and not subject to “metaphysical doubt”.

Now what is a psychological certainty when it comes to a certain proposition?

“[W]e cannot conceive of its being false except on the rather extravagant supposition that even when we perceive it as true we are being deceived by some very powerful demon.”

Now what is something that we can call epistemological certainty?

“Those clear and distinct perceptions that we cannot be conceived to be false even on this demon hypothesis”

Psychological certainty isn’t metaphysical certainty. Psychological certainty is suspect to metaphysical doubt. Epistemological certainty isn’t metaphysical doubt. Epistemological certainty is based on metaphysical certainty, which comes from a faculty of the mind known as “light of nature” or “natural light”. We now have two levels or certainty.

These two levels of certainty have a corresponding of two levels of doubt.

[1.] There is metaphysical doubt, which is a proposition being conceived to be false on the demon hypothesis, and can be conceived to be false even without the demon hypothesis. For example, we can think that there is a world of corporeal things, like a chair, that exists independent of the person. This is called under question by the demon-hypothesis. But, we can also call into doubt something like I went to the grocery store yesterday, which we don’t need the demon-hypothesis to call into question because we are not even psychologically certain. So metaphysical doubt is brought up when something can be false under the demon-hypothesis, which is something that is psychologically certain, or called false even when we ignore the demon-hypothesis and aren’t psychologically certain about it.

[2.] There is metaphysical certainty, which is a proposition that can’t be conceived of being false, even under the demon hypothesis (metaphysical doubt). These positions are what are given to use through the “light of Nature”. We can come to know that we exist, and this is metaphysically certain. Not even the demon hypothesis could change our minds of this. Thus, it is metaphysically certain and also epistemologically certain. He also comes to hold that God is part of these beliefs that are metaphysically certain and so epistemologically certain.

One of the things about Descartes idea is that any system that has metaphysical certainty must be based on premises that are given to us through the light of nature, and this would mean that we would have to exclude things, no matter how psychologically certain we are of them, even if we take it to be extravagant that we would have to give them up because they’re not given by the light of nature.

One of the examples of a conclusion that Descartes comes to, through the light of nature, is the Cogito of “I think, therefore I exist”. For example, he goes on to say that “the natural light…has shown me that I am from the fact that I doubt…Then without doubt I exist also if he [the demon] deceives me, and let him deceive me as much as he will, he can never cause me to be nothing so long as I think that I am something.”

Descartes comes to find, through natural light, that he exists and this cannot be doubted. This not being able to be doubted, makes it both metaphysical certain and also epistemologically certain. Descartes also goes on point out the thinking being, Descartes, has within him the idea of God, which contains all God’s attributes that are known through the light of nature alone. He comes to this conclusion based on something else that natural light gives to him.

“Now it is manifest by the natural light that there must at least be as much reality in the efficient and total cause as in its effect…Thus the light of nature causes me to know clearly that the ideas in me are like pictures or images which can, in truth, easily fall short of the perfection of the objects from which they have been derived, but which can never contain anything greater or more perfect.”

Descartes comes to the conclusion that he exists, which is based on metaphysical certainty, which happens by the light of nature. He also comes to the conclusion that there must be as much reality in the efficient and total cause as in its effect. This is also known by natural light. He finds that many of his ideas can be formed from what exists already in himself, by the light of the axioms that the effect contains as much reality as the cause, except for one. Through a process of elimination, he finds that he can’t conceivably have formed from what already exists within himself, yet he has the idea of God who contains this ability.

Descartes says that “Because the light of nature makes it very clear that whoever knows something more perfect than himself cannot be the author of his being, because then he would have given himself all the perfections of which he had cognizance…”

From all of this, Metaphysical certainty shows that if he was created at some point in time, then he must have been created by God. Descartes says that “I see nothing in all that I have just said which by the light of nature is not manifest to anyone who desires to think attentively on the subject.”

But Descartes has to make one further point.

“But thought I assume that perhaps I have always existed just as I am at present, neither can I escape the force of this reasonings, and imagine that the conclusion to be drawn from this is, that I need not seek for any author of my existence…For…in order to be conserved in each moment in which it endures, a substance has need of the same power and action as would be necessary to produce and create it anew, supposing it did not exist, so that the light of nature shows us clearly that the distinction between creation and conservation is solely a distinction of the reason.”

These things help lead to his cosmological argument for the existence of God. These were all based on, what Descartes calls, “light of nature” or “natural light”. These things were said to be based on metaphysical certainty, or epistemological certainty.

Descartes also comes up with this ontological argument, and there is supposed to be a detailed account of the argument in his Fifth Meditation. This meditation compares God’s property of existence with properties possessed by numbers and geometrical figures. However, there is a difference between those of mathematics and that of God. The one of God is known through natural light, while that of mathematics isn’t. The reason is that Descartes evil-demon even called into question mathematics, like “angles of a triangle are equal to two right angles”. This was called into question by the evil-demon, even though the idea of triangles is psychologically certain.

“The reason for comparing the existence of God with various properties of mathematical entities is to explain how existence is inseparable from God’s nature. Descartes’ purpose is not to suggest that we have the same level of certainty about God’s properties and the properties of mathematical entities. The latter are among the things subjected to metaphysical doubt earlier in the Meditations; their reliability is shown only after it has first been shown that God exists. The properties of God, on the other hand, are known by the light of nature and are not subject to metaphysical doubt…It is inconceivable that God should not have the property of existence, just as it is inconceivable that a triangle should not have three sides. And yet the inconceivability is not exactly the same in the two cases. For we can suppose that triangles need not be three-sided and that we are being deceived into thinking that they must be three-sided. But we cannot be deceived with respect to what we know through the light of nature, such as that existence is necessarily a property of God.”

What is being brought up here is that Descartes does not exclude the possibility of the existence of God being known with greater certainty than those attributes of mathematics. The latter are known through psychological certainty, and the former are known through the light of nature, which is metaphysical certainty.

So Ross comes to conclude that “for Descartes the ontological argument rests only on premises which are given by the light of nature. This means, since it is impossible for him to doubt or in any way pretend that the things known by the light of nature are false, that the ontological argument is metaphysically certain, and that it is therefore equivalent to the cosmological argument in certainty.”

Descartes also once said that “it is incumbent on us to imagine that he is a deceiver if we wish to cast doubt upon our clear and distinct perceptions.” Ross suggests that “no contrary reason” could cast doubt upon the truth of clear and distinct perceptions is that “they were only open to metaphysical doubt under the demon hypothesis”. However, now that Descartes has reached God, he can now say that all clear and distinct perceptions are true.

What happens is this: Some clear and distinct perceptions are metaphysically certain even with the Demon hypothesis. Some clear and distinct perceptions are metaphysically doubtful with the Demon hypothesis. Those clear and distinct perceptions that are metaphysically certain, with the Demon hypothesis, allow us to combine them to each other to reach the existence of God. Applying metaphysically certain ideas only leads to other metaphysically certain ideas, which becomes that of the existence of God. And this is known by natural light, and also that God is no deceiver. Now those clear and distinct things that could be doubted under the Demon hypothesis can no longer be doubted, because God has banished this demon away by God’s very existence, and this leads to all clear and distinct perceptions are metaphysically certain. In other words, those that clear and distinct perceptions that were in metaphysical doubt, turn out to be metaphysically certain once it is found that there is no deceiver.

Descartes makes a reply to an alleged circularity with is Clear and Distinct idea and God.

“…when I said that we could know nothing with certainty unless we were first aware that God existed, I announced in express terms that I referred only to the science apprehending such conclusions as can recur in memory without attending further to the proofs which led me to make them. Further, knowledge of first principles is not usually called science by dialecticians. But when we become aware that we are thinking beings, this is a primitive act of knowledge derived from no syllogistic reasonings. He who says, ‘I think, hence I am, or exist’, does not deduce existence form thought by syllogism, but, by a simple act of mental vision, recognizes it as if it were a thing that is known per se.”

Ross comes to a conclusion like this, based on what has been said before.

“[Descartes] is placing some limitation on the clear and distinct perceptions whose truth is first established after the existence of God is proved. Not all clear and distinct perceptions depend upon our knowing that there is a God, but only those that are in some unspecified conclusions of demonstrations, as opposed to the sort of first principles that one recognizes “by a simple act of mental vision…as if it were a thing that is known per se.” I take these first principles known per se to be metaphysically certain principles given by the light of nature, and I suggest that “such conclusions as can recur in memory without attending further to the proofs which led me to make them” is his way of referring to those clear and distinct perceptions not given by the light of nature. For in metaphysics the light of nature provides the only perceptions whose truth is completely and independently certain and need to be demonstrated. And the truth of the of the remaining clear and distinct perceptions, since they are subject to the demon hypothesis and to metaphysical doubt, needs to be demonstrated from the existence of a benevolent God. We are metaphysically certain that they are true only so long as we remember that their truth was metaphysically demonstrated from first principles known per se. When we do not remember this demonstration (which involves the demonstration of the existence of a God who would not deceive us with respect to our clear and distinct perceptions), these clear and distinct perceptions are once more subject to the demon hypothesis and thus lack metaphysical certainty. If this is Descartes’ meaning, he is clearly justified in rejecting the charge of circularity.”

Ross, in concluding the paper, makes a certain point. He finds that Descartes can escape the charge of circularity, but Ross things that there is another possible problem, as he has interpreted Descartes. He points out that he has not really shown that some of his other metaphysically certain positions, besides his “questionable” “I think, therefore I exist”, withstand the Demon hypothesis. Ross, in fact, goes on to think that his other metaphysically certain premises even fall to the demon hypothesis, which would make them metaphysically doubtful. Ross says this because Descartes usually produces this claim of a certain proposition being known by the “light of nature”, and never really offers any argument to support these metaphysically certain positions that he knows by the “light of nature”.

As Ross says, “from then on (after getting the cogito ergo sum principle) he smuggles in one crucial premise after another without ever attempting to establish the metaphysical certainty of even one. The result is that his metaphysics is based upon a great many premises whose “metaphysical certainty” is at best highly questionable, and at worst non-existent. This, rather than circularity, is the basic flaw in Descartes’ work.” I, myself, might add one thing in this regard. Descartes held that we have some innate ideas, and so these innate ideas would appear to be what is known by “light of nature”. So he doesn’t, in some sense, have to defend these premises that are known by the “light of nature”. This would be consistent with his whole system. So one can question these innate ideas if they want to attack his system.